The Smoking Pack Year Calculator calculates the number of pack years which is a way to measure the amount of tobacco a person has smoked over a long period of time. One pack year is defined as 20 manufactured cigarettes per day smoked everyday in the course of one year. All other types of tobacco products have their cigarette equivalents, so it is possible to use pack years as a measure of smoking intensity for clinical purposes.
To calculate a smoking pack years just fill in the appropriate fields of the calculator and click the “Calculate” button. In case you changed your smoking habits over the years (say, smoked 2 packs of cigarettes per day for 5 years, then smoked 1 pack per day for the next 10 years) you can click the “+” symbol on the right hand side to get additional fields, or the “–” symbol to delete them. Please note that tobacco should be specified as amount smoked per week.
Pack Years of Smoking
Calculating smoking pack years is a way to measure a person’s tobacco use over time. It is important because it can help healthcare providers assess a person’s risk of developing tobacco-related health problems, such as lung cancer, heart disease, and chronic obstructive pulmonary disease (COPD).
To calculate pack years, you need to know how many cigarettes a person smoked per day and for how many years they smoked. Pack years are calculated by multiplying the number of standard packs of cigarettes smoked per day by the number of years the person smoked:
where Packs is the number of standard packs smoked daily (average):
where
Number of cigarettes is the number of cigarettes smoked daily (average),
Pack size is 20 cigarettes (standard pack).
In the case of other tobacco products, you can use the cigarette equivalent in the above formulas.
In our Smoking Pack Year Calculator we use some estimations for cigarette equivalent of different types of tobacco products. Specifically we assume that
• one cigarillo is equivalent to 2 cigarettes,
• one cigar is equivalent to 4 cigarettes,
• one pipe is equivalent to 2½ cigarettes.
Loose tobacco estimation is that 25 grams (1 oz) is equivalent to 50 cigarettes.
According to a World Health Organization study on waterpipe smoking a 20-minute session of waterpipe smoking is equivalent to 25 cigarettes.
As noted above, using pack years as a measure of lifetime tobacco exposure helps physicians calculate the probable risk of lung cancer as well as risks of many other conditions associated with smoking. In general, the more pack-years a person have smoked, the greater the chance of getting the disease. More intense smoking, measured in pack‐years, is associated also with decreased survival after a diagnosis of some types of lung cancer. It is worth to note that the relationship between pack years of smoking and lung cancer has statistical nature, and don’t always applicable to individual people.
In this connection it’s important to note that these calculations are estimates only and may not be entirely accurate. Pack years may not take into account other factors that can affect a person’s risk of developing tobacco-related health problems, such as the type of tobacco used and the person’s overall health and lifestyle.
On the other hand, pack years calculation can not only help healthcare providers assess a person’s risk of tobacco-related health problems and determine the best course of treatment. It can also help people who are trying to quit smoking understand the impact of tobacco use on their health and motivate them to quit.
Example of Smoking Pack Years Calculation
Consider the example of a person who smoked an average of 5 cigarettes every day for the first 4 years since he began smoking. Then for the next 10 years of his life, he smoked one pack of cigarettes daily. After that, for the next 6 years, he smoked 4 pipes every day. How many pack-years did he smoke during all that time?
Using the above formulas we can get:
Pack years = (5 cigarettes) / (20 cigarettes per pack) × 4 years + (1 pack of cigarettes) × 10 years + ((4 pipes) × (2.5 cigarettes)) / (20 cigarettes per pack) × 6 years,
where we took into account that one pipe is equivalent to 2.5 cigarettes. Carrying out further calculations, we get:
Pack years = 1 + 10 + 3 = 14.
Thus, the measure of this person’s exposure to tobacco over 20 years of smoking is 14 pack years.
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Check out our other health calculators such as Blood Alcohol Level Calculator or Standard Drinks Calculator.
Disclaimer. Please remember that this calculator is intended for education use only. It is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your doctor for advice about your specific medical condition.